Digital polar transmitter (DPTX) architectures are very attractive for modern radios because they can provide improved area and power consumption characteristics compared with conventional analog architectures. Digital-to-time converters (DTCs) can be used to generate frequency or phase modulated signals in digital polar transmitters. Existing DTCs are built with a chain of inverters, made of a coarse resolution chain and some interpolating structures for fine resolution. As such, DTCs can suffer from two main issues. First, the delay generated by the coarse resolution can strongly depend on Process-Voltage-Temperature (PVT) variations, which can hardly be corrected by calibration. Second, poor spectral purity of the generated clock can result from thermal noise and flicker noise generated by inverters in the chain.